Add Nuget publish job with Trusted Publishing (test registry)

Author: chrisyarbrough

.github/workflows/release.yml

@@ -59,4 +59,48 @@ jobs:
         generate_release_notes: true
         prerelease: true
         draft: true
-        make_latest: true
+        make_latest: true
+
+  publish-nuget:
+    if: startsWith(github.ref, 'refs/tags/')
+    needs: build
+    runs-on: ubuntu-latest
+    permissions:
+      id-token: write  # enable GitHub OIDC token issuance for this job
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v4
+
+    - name: Setup .NET
+      uses: actions/setup-dotnet@v4
+      with:
+        dotnet-version: '10.0.x'
+
+    - name: Pack NuGet package
+      working-directory: src/ucll.build
+      run: |
+        PACK_DIR=bin/pack
+        BUILD_DIR=$PACK_DIR/build
+        dotnet pack ../ucll/ucll.csproj \
+          -p:PackAsTool=true \
+          -p:ToolCommandName=ucll \
+          -p:PackageId=UnityCommandLineLauncher \
+          -p:Authors="Chris Yarbrough" \
+          -p:PackageLicenseExpression=MIT \
+          -p:PackageReadmeFile=README.md \
+          -p:PackageTags="Unity CLI Hub" \
+          -p:RepositoryUrl=https://github.com/chrisyarbrough/UnityCommandLineLauncher \
+          -p:RepositoryType=git \
+          -p:OutputPath=$BUILD_DIR \
+          -p:PublishDir=$BUILD_DIR \
+          --output ../ucll/$PACK_DIR
+
+    - name: NuGet login (OIDC → temp API key)
+      uses: NuGet/login@v1
+      id: login
+      with:
+        user: ${{ secrets.NUGET_USER }}
+
+    - name: NuGet push
+      run: dotnet nuget push src/ucll/bin/pack/UnityCommandLineLauncher.*.nupkg --api-key ${{ steps.login.outputs.NUGET_API_KEY }} --source https://apiint.nugettest.org/v3/index.json